Additive Prognostic Value of PALS Compared to Bernard's Staging in Patients Undergoing MV Surgery

Mitral valve prolapse is the most common cause of mitral regurgitation requiring surgery in developed countries. While cardiac surgery is recommended for symptomatic patients, in accordance with the ESC guidelines on valvular heart disease, indications for intervention in asymptomatic patients are mainly based on two-dimensional echocardiographic criteria: the presence of left ventricular systolic dysfunction or dilatation (end-systolic diameter ≥ 40 mm and/or ejection fraction ≤ 60%); or, in patients with preserved left ventricular systolic function, the occurrence of atrial fibrillation secondary to valvular disease or pulmonary hypertension (systolic pulmonary artery pressure > 50 mmHg); finally, significant left atrial dilatation (indexed left atrial volume ≥ 60 ml/m² or diameter ≥ 55 mm) also represents an indication. Mitral valve repair is preferred over valve replacement with a prosthesis, as it is associated with lower intraoperative mortality, better long-term survival, and fewer valve-related complications. However, the cut-off values derived from conventional echocardiography and used as indicators for surgical intervention may reflect an already severe and irreversible structural and functional cardiac alteration. Moreover, they do not consider more advanced imaging techniques such as speckle tracking echocardiography, which is now widely used in clinical practice and allows for a quantitative assessment of myocardial function through the analysis of myocardial fiber shortening in the cardiac walls. Several studies have shown that preoperative peak left atrial longitudinal strain (PALS) has prognostic value in predicting postoperative clinical outcomes in patients undergoing surgery for primary mitral regurgitation, as well as in predicting left atrial reverse remodeling; this prognostic relevance has also been observed in asymptomatic patients and in cases of less than severe mitral regurgitation. Furthermore, Bernard et al. demonstrated the prognostic value of a staging system for extra-valvular cardiac damage, assessed using two-dimensional echocardiographic data, in asymptomatic patients with moderate or severe mitral regurgitation.